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Example 1: Pack a Paradox or dBASE table.

 

This example will pack a Paradox or dBASE table therefore removing already deleted rows in a table. This function will also regenerate all out-of-date indexes (maintained indexes). This example uses the following input:

 PackTable(Table1)

 

The function is defined as follows:

 

// Pack a Paradox or dBASE table

// The table must be opened exclusively before calling this function...

procedure PackTable(Table: TTable);

var

 Props: CURProps;

 hDb: hDBIDb;

 TableDesc: CRTblDesc;

begin

 // Make sure the table is open exclusively so we can get the db handle...

if not Table.Active then

  raise EDatabaseError.Create('Table must be opened to pack');

if not Table.Exclusive then

  raise EDatabaseError.Create('Table must be opened exclusively to pack');

 

 // Get the table properties to determine table type...

 Check(DbiGetCursorProps(Table.Handle, Props));

 

 // If the table is a Paradox table, you must call DbiDoRestructure...

if Props.szTableType = szPARADOX then begin

   // Blank out the structure...

   FillChar(TableDesc, sizeof(TableDesc), 0);

   // Get the database handle from the table's cursor handle...

   Check(DbiGetObjFromObj(hDBIObj(Table.Handle), objDATABASE, hDBIObj(hDb)));

   // Put the table name in the table descriptor...

   StrPCopy(TableDesc.szTblName, Table.TableName);

   // Put the table type in the table descriptor...

   StrPCopy(TableDesc.szTblType, Props.szTableType);

   // Set the Pack option in the table descriptor to TRUE...

   TableDesc.bPack := True;

   // Close the table so the restructure can complete...

   Table.Close;

   // Call DbiDoRestructure...

   Check(DbiDoRestructure(hDb, 1, @TableDesc, nil, nil, nil, False));

end

else

   // If the table is a dBASE table, simply call DbiPackTable...

  if (Props.szTableType = szDBASE) then

     Check(DbiPackTable(Table.DBHandle, Table.Handle, nil, szDBASE, True))

  else

     // Pack only works on PAradox or dBASE; nothing else...

    raise EDatabaseError.Create('Table must be either of Paradox or dBASE ' +

       'type to pack');

 

 Table.Open;

end;